Wastewater Treatment Works - Primary and Biological Treatment

Veolia Water Solutions & Technologies are constructing a major new process plant at Peacehaven Wastewater Treatment Works, part of Southern Water's multimillion environmental project to bring cleaner seas to Sussex.

The works, being built by 4Delivery Limited, will treat wastewater for a population equivalent of circa 300,000, using Veolia's Multiflo lamella clarifiers for primary treatment and Biostyr for biological secondary treatment.

The fat, oil, grease and grit removal system consists of three identical aerated concrete channels, each 25.75m long x 5m wide and fitted with chain and flight scrapers which remove settled solids from the bottom of the channel whilst also removing grease and other non-settling debris from the top via a scum tube.

Primary treatment for the 95Ml per day flow is carried-out by settlement using Multiflo lamella clarifiers. Peacehaven is the first UK Multiflo lamella system to incorporate both automatic lamella plate cleaning and an automatic scum removal system. A lamella block system was also adopted to speed up the installation of the plate packs.

Secondary treatment uses a battery of ten Biostyr biological aerated flooded filters. These compact filters will provide removal of COD and BOD as well as eliminate suspended solids and particulate pollutants to give a high clarity effluent for discharge to the sea. The Biostyr air blowers and internal air grids are installed and all the nozzles have been fitted to the nozzle slab. Air flow distribution pipework and the feed and backwash pipework, which were all fabricated on site, have been fitted in the gallery where all ten units are ready for media installation.

The project is being carried out by 4Delivery, which is a consortium comprising Veolia Water, Costain and MWH, and is also carrying out aprogramme of environmental improvement and water quality schemes for Southern Water across Kent, Sussex, Hampshire and the Isle of Wight, in addition to the Cleaner Seas for Sussex Scheme.